Direct-current relay



March 31, 1931. CRICHTQN ET L 1,798,659

DIRECT CURRENT RELAY 1925 2 Sheets-Sheet 1 Filed Aug. '25

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DIRECT CURRENT RELAY Filed Aug. 25, 1925 2 Sheets-Sheet 2 INVENTORS Zea/12s A. Cr/cfon & BY \/afi/7 Kine/34y.

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Patented Mar. 31, 1931 UNITED STATES PATENT OFFICE LESLIE N. CRICHTON AND JOHN V. BREISKY, OF PITTSBURGH, PENNSYLVANIA, AS- SIGNORS TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A COR- PORATION OF PENNSYLVANIA DIRECT-CURRENT RELAY Application filed August 25, 1925. Serial No. 52,842.

O-ur invention relates to relays and particularly to direct-current relays.

One object of our invention is to provide an improved polarized or reverse-current relay.

Another object of our invention is to provide a sensitive direct-current relay having an adjustable operating-time characteristic.

Another object of our invention is to provide a relay having an armature member and a field-magnet structure comprising a polarized magnet and a winding cooperating therewith to control the movement of the armature member. I

A further object of our invention is to provide a relay having a field-magnet structure comprising a polarized magnet, soft-iron pole pieces secured to the magnet and a winding so disposed on the pole pieces that the operation of the relay is effected without demagnetization of the polarized magnet.

Other objects and advantages of our invention will appear from the following detailed description of a relay constructed in accordance therewith. I

In the accompanying drawings,

Figure l is a plan View of a relay embodyingthe invention, parts of the casing and frame being broken away in order to show the construction of the armature member and field magnet more clearly;

Fig. 2 is a front view of the relay shown in Fig. 1;

Fig. 3 is a side view, partially in section, of the relay shown in Figs. 1 and 2; and

Fig. 4 is a. simplified diagram of the arrangement of the field-magnet structure and armature member.

The relay shown in the drawing comprises a frame member 1 upon which a vertical spindle or shaft 2 is pivoted in bearings 3 and 4. An armature member 5 and a disc member 6 are mounted upon the shaft 2. A field-magnet structure 7 cooperates with the armature member 5. A permanent magnet 8 cooperates with the disc member 6 to damp the movements thereof. The damping magnet 8' may be omitted if it is desired that the relay shall have an instantaneous operating-time characteristic.

aperture in a circular disc member 11 of nonmagnetizable metal. The thickness and configuration of the magnetizable armature member 10 depends upon the desired operating characteristics of the relay. The thickness of the disc member 11 is preferably such that the weight per unit area is the same as that of the armature member 10. Since the armature member 10 is mounted in an aperture in the disc member 11 and the two members are of equal weight per unit area, the composite armature member comprising the magnet-izable and non-magnetizable portions 10 and 11 is balanced upon the spindle 2 and, therefore, the bearings 3 and 4 may be delicate and substantially frictionless.

' The relay is also free from errors resulting from an unbalanced moving element. As shown in Fig. 3, the upper bearing 3 may be of the pin type, since the moving element comprising the shaft 2 and the elements supported thereon is substantially balanced. The bearing comprises a pin 12 in the upper end of the shaft 2 engaging the stationary bearing member 13 on the frame.

The lower bearing 4 comprises a steel ball 15 disposed between sapphire or other jewel bearings 16 and 17 on the spindle and frame respectively. The provision of a balanced moving element and frictionless bearings in the relay reduces the errors from friction or unbalanced masses. I

The field-magnet structure 7 comprises a polarized magnet 20 having soft-iron pole pieces 21 and 22 secured to the upper and lower ends thereof, (see Figs. 1 and The lower pole piece 22 is split into two parallel portions 23 and 24 on which are disposed windings 25. The tips of the lower pole piece are preferably separated by a considerable air gap, as indicated at 26, to reduce the leakage flux and to increase the torque on L the armature member 5.

As shown in Fig. 4, the parallel portions 23 and 24 of the lower pole piece22 terminate adjacent to the armature member 10 on the opposite side thereof from the upper pole piece 21. The winding 25 is wound in opposite directions upon the portions 23 and 2% of the split pole piece 22.

The polarizing magnet polarizes the pole pieces2l and 22 when the winding is deenergized, the flux from the magnet dividing equally between the portions 23 and 2a of the split pole piece 22. When the winding 25 is energized, the magnetic flux traversing one of the parallelportions' 23and 24 is strengthened and that traversing the other portion is weakened, dependingupon the direction of the current traverslng the w1nd-' two portions'23 and 24 of the split pole piece 22. A movable" contact member 29 is secared to the spindle 2 and is adapted to cooperate Withistationarycontact members 30 and 31 depending-upon thepolarity of the'currenttraversing the winding 25. The balance ing disc 11 is preferably arranged to bal ance the weight of the contact member 29.

If the relay is to be used as a reverse-current relay, the spring 28 is so arranged as to hold the movable contact member 29 in engagement with: the stationary contact mem ber 30, asshown in Figs. 1 and 2. The winding 25 is so:connected inithis instance as to attract'the armature member 10 into the position shown in Fig. 1. when the polarity of the circuit is normal; When the polarity reverses, the armature member 1-0 is attracted by the-portion 24 of the'field magnet structure and the movable contact member 29 is actuated 1 in a counter-clockwise direction the :fixedr contact members 31.

The fixed contact members 81 are supported on a pivoted arm 32 (see Figs. land 2) which may be turned about the axis of the shaft 2. The adjustment of the arm 32 changes the spacing of the contact members 29 and 31 and thereby changes the operating time of the relay since-the 'movementof the armature member is damped by the damping magnet 8. A scale SSmay be provided for cooperation with the movable :arm 32 to facilitate the time-adjustment oftherel'ay and to" indicate the timesetting after the relay has'been adjusted.

A magnetic shieldB lof iron is interposed between the armature'5 and the-damping magnet 8 to eliminate the effect of the field of the magnet upon the armature.

The relay describedhas provedtobe exceedingly sensitive, reliable and permanent in v armature member. against the spring 28 1ntorengagement with ture and damping means upon a single shaft,

with the entire moving element mechanically balanced, decreases the losses and errors involv ed to such an extent that a marked increase in sensitivity is obtained. If desired, the armature member 10 and other elements of the relay mayibe made of silicon iron or a similar alloy having-substantially'no residual 'magnetism.

Manyrha'nges in the construction of the specific relay shown and described above within the scope of the invention will occur to'those skilled in the'art'and consequently our invention is not to be'limited in: scope except as may beindicated'in the appended claims.

We claim as ourinventionz+- Y 1. A relay comprising a pivoted shaft, a magnetizable armature member supportedby said shaft, a polarized field magnet having a split pole piece cooperating withsaid armature member, windings on therespective portions of said split pole piece for controlling the armature member and means for magnetically. damping the movements of said armature member. l

2. A relaycompri sing a pivoted. shaft, a magnetiz able armature'member supported by said shaft, a polarized field 'Ina'gnet, pole pieces secured to said magnet and disposed on opposite sides of said armature member, a windin on one of saidpolefpie'ces for'controlling the armature member and means for magnetically damping the movements of said 3. A relay comprising a vertical shaft, a magnetizable armature member of'diskrshape 'eccentrica'lly' supported thereby for movement in a horizontal plane, a polarized field magnet, upper and lower pole pieces secured to said field magnet and disposed above and below said armature member to hold said member normally in a predetermined position, and windings on said pole pieces'for abtuating saidarmature member from the normal position.

4; A relay comprising a vertical shaft, a magnetizable armature member of disk shape supported thereby for movement in-a horizontal plane, a polarized field magnet, a pole other end of said field magnet and disposed on the opposite side of saidarmature member and windings on the respective portions of said split pole piece for controlling said armature member.

5. A polarized relay comprising a polarized field magnet having a pole piece of one polarity and a plurality of pole pieces of the opposite polarity adjacent said pole piece, a disk-shaped magnetizable armature mounted for substantial rotary movement between said pole pieces of opposite polarity, and means for varying the effect of the said pluiallty of pole pieces on said armature mem- 6. A polarized relay comprising a movable magnetizable armature member, a polarized field magnet therefor having a projecting pole piece of one polarity disposed on one side of said armature member and a plurality of pole pieces of the opposite polarity on the opposite side thereof, an armature disk disposed between the pole pieces for horizontal rotary movement, and a winding on said pole pieces, said pole pieces being so arranged that the armature member is actuated in one direction or the other depending upon the direction of the current traversing said windmg.

7. An electric relay comprising a magnetizable core and an armature therefor consisting of a magnetizable disc eccentrically mounted upon a rotatable shaft and a counter-balancing non-magnetizable disk provided with an opening into which the magnetizable disc fits.

8. An electric relay comprising a polarized core member provided with a bifurcated horizontally extending upper pole piece of one polarity and two horizontally extending lower pole pieces adjacent thereto but of the r opposite polarity, a vertical shaft mounted for rotary movement, and an armature supported thereon and disposed between the upper and the lower pole pieces, and consisting of a magnetizable disc eccentrically mounted upon the shaft.

9. An electric relay comprising a magnetizable core provided with one pole piece at one end and two separated pole pieces for the other end disposed adjacent the first pole piece, and a magnetizable armature disk eccentrically mounted upon a shaft for rotary movement between the single pole piece and the other two depending upon which of said two pole pieces is predominatingly energized.

10. An electric relay comprising a magnetizable core provided with one pole piece at one end and two separated pole pieces for the other end disposed adjacent the first pole piece, a magnetizable armature disk eccentrically mounted upon a shaft for rotary movement between the single pole piece and the other two depending upon which of said two pole pieces is predominatingly energized, and damping means for said disc consisting of a second disk mounted upon said shaft and LESLIE N. CRICHTON. JOHN V. BREISKY. 

